An article on pages 74-82 of the periodical "Olhydraulik und Pneumatik" 26 (1982) No. 2 concerns a hydraulic drive system comprising a first hydraulic machine with adjustable volume of through-put capable of working as a pump or motor, a line of load-independent pressure to which said first machine is connected, a second hydraulic machine as a signal transmitter capable of working as a motor or pump in response to the direction of rotation of said first machine to produce a control flow proportional to the actual speed of the first machine to which the second machine is mechanically coupled, and a flow restricting system including a pump and an adjustable throttle which system in combination with the control flow of said signal transmitter delivers a pressure signal p.sub.st which is compared with a predetermined pressure p.sub.O, wherein the control device for setting the volume of through-put of said first machine is activated in response to the differential pressure p.sub.st -.sub.O. Such drive system is capable of working in a four-quadrant operation i.e. the system is capable of delivering as well as receiving energy in both directions of rotation. It is an object of the present invention to improve the speed control to obtain a reaction rate as fast as possible. It is a further object to dampen and to stabilize the control process to avoid heavy transient response.